Young Patients with Suspected Uncomplicated Renal Colic are Unlikely to Have Dangerous Alternative Diagnoses or Need Emergent Intervention

Abstract

IntroductionIn the United States there is debate regarding the appropriate first test for new-onset renal colic, with non-contrast helical computed tomography (CT) receiving the highest ratings from both Agency for Healthcare Research and Quality and the American Urological Association. This is based not only on its accuracy for the diagnosis of renal colic, but also its ability to diagnose other surgical emergencies, which have been thought to occur in 10–15% of patients with suspected renal colic, based on previous studies. In younger patients, it may be reasonable to attempt to avoid immediate CT if concern for dangerous alternative diagnosis is low, based on the risks of radiation from CTs, and particularly in light of evidence that patients with renal colic have a very high likelihood of having multiple CTs in their lifetimes. The objective is to determine the proportion of patients with a dangerous alternative diagnosis in adult patients age 50 and under presenting with uncomplicated (non-infected) suspected renal colic, and also to determine what proportion of these patients undergo emergent urologic intervention.MethodsRetrospective chart review of 12 months of patients age 18–50 presenting with “flank pain,” excluding patients with end stage renal disease, urinary tract infection, pregnancy and trauma. Dangerous alternative diagnosis was determined by CT.ResultsTwo hundred and ninety-one patients met inclusion criteria. One hundred and fifteen patients had renal protocol CTs, and zero alternative emergent or urgent diagnoses were identified (one-sided 95% CI [0–2.7%]). Of the 291 encounters, there were 7 urologic procedures performed upon first admission (2.4%, 95% CI [1.0–4.9%]). The prevalence of kidney stone by final diagnosis was 58.8%.ConclusionThis small sample suggests that in younger patients with uncomplicated renal colic, the benefit of immediate CT for suspected renal colic should be questioned. Further studies are needed to determine which patients benefit from immediate CT for suspected renal colic, and which patients could undergo alternate imaging such as ultrasound.

Internal validation of a scoring system to evaluate the probability of ureteral stones: The CHOKAI score

“…Many reports point out that cumulative radiation exposure increases cancer risk, and young patients are at a higher risk from diagnostic X-rays than adults [5,21]. Schoenfeld et al indicated that in younger patients with uncomplicated renal colic, the benefit of immediate CT for suspected renal colic is questionable [22]. Nevertheless, nearly six out of seven patients with a diagnosis of renal colic in the emergency department still underwent a CT scan, and in patients with previous ED visits for renal colic, the CT rate was still 59% [20].…”

Derivation of decision rules to predict clinically important outcomes in acute flank pain patients

“…The addition of renal point-of-care limited ultrasonography modestly improved risk stratification of the STONE score [31]. Age and elevated white blood cell count are known predictors of ureteral stone requiring urologic intervention [17,32]. A prior history of kidney stone is known to increase the risk of ureteral stone in patients with suspected kidney stone [33].…”

“…We reviewed prior studies of clinical decision rules and studies identifying predictors of ureteral stones requiring intervention or serious alternative diagnoses [7,16–19]. Important predictors of stone requiring urologic intervention from the literature review included stone size, stone location, pain level, signs of urinary tract infection (elevated white blood cell count, leukocyte esterase and nitrites on urinalysis), and age.…”

A comparative, epidemiological study of acute renal colic presentations to emergency departments in Doha, Qatar, and Melbourne, Australia

“…Such differences may have marked implications for the applicability of available evidence. As shown in meta-analyses and systematic reviews, renal colic due to stone size 5–10 mm in the lower ureter may benefit more from tamsulosin use by facilitating stone passage than the stones located higher in the urinary tract or with size out of this range [ 15 , 16 ]. Therefore, we recommend increased use of tamsulosin for patients in Qatar who have larger stone size 5–10 mm in the lower ureter to get maximum benefits of MET [ 7 , 8 , 17 ].…”